Interest Expense (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Interest Expense [Abstract]
Interest expense before capitalized interest	$ 18,274	$ 17,911	$ 52,751	$ 60,758
Amortization of deferred financing costs	857	698	2,255	2,576
Interest expense related to finance lease right-of-use assets	464	230	1,026	691
Net unrealized loss on derivative financial instruments not designated as cash flow hedges	202	2	173	50
Capitalized interest	(2,912)	(8,258)	(11,545)	(23,211)
Interest Expense	$ 16,885	$ 10,583	$ 44,660	$ 40,864